Frequency multiplication



July 1o, 1934. R. GURTLER 1,965,641

, AFREQUENCH; MULTIPLIACATIONA Filed Dec'. 6, 195o VT f1 mmnnmm INVENTOR RUDOLF GURTQER Patented July 10, 1934 y UNITED STATES 1,965,641 FREQUENCY MUL'rlrucA'rroN Rudolf Grtler, Berlin, Germany, assignor to Telefunken Gesellschaft fr DrahtloseA Telegraphie m. b. ll., Berlin, Germany, a corpora.-

tion of Germany Application December 6, 1930, Serial No. 500,524 In Germany December 6, 1329 7 Claims. (Cl. 172-281) This invention relates to an arrangement for frequency multiplication by means of valves a'nd is more fully described in connection with the accompanying drawing wherein Figures 1 and 2 illustrate respectively a frequency changer and a characteristic curvetherefor; Figures 3 and 4 are similar to Figures 1 and 2 but refer to the present invention, and, Figures 5 to 8 inclusive illustrate some modifications of the present invention.

It is known in the prior art that valves, for instance, high-vacuum rectifiers, mercury-vapor hot-cathode rectiiiers, etc., when operated under certain conditions to rectify a given alternating current, distort the current so that several alternating current components of different frequencies appear in the output circuit.' These valves, therefore, are useful for frequency changing. Figure l shows the basic principle of such 3 a scheme. This system comprises a fundamental frequency source and one valve V or a group of paralleled units in series with a circuit coupled to said source. This circuit also includes tuning means C, L for selecting a desired component and transferring the same to a load circuit shown for purposes of illustration as an antenna. Figure 2 shows the shape ofthe current passed by the valve to the output circuit thereof plotted against time units. It can be 3 seen therefrom that the resulting current contains a direct current component..

The same situation is true of all other circuit arrangements of this type known heretofore in the art, for invariably a direct current component will flow through the output circuit. In the case of rectification work this is desirable and is very important, though being troublesome and undesirable in the case of frequency-changing Work.

Now, according to this invention two valves V. V" are connected in parallel and opposition in the circuit interposed between the alternating current source and load as shown in Figure 3 instead of a single valve, as shown in Figure 1. Both valves V', V" (or groups comprising a plurality of such units) are so associated that the cathode of one valve is directly connected with the anode of the other valve. When alternating current is impressed on these valves a current will flow in said circuit having a form similar to that shown in Figure 4. In other words, it will no longer consist of unidirectional current impulses, but rather of alternating current without a direct current component. In Figure 3 CnL' is the output or oscillation circuit which is tuned to the useful frequency. This circuit may be tuned to the third harmonic of the fundamental wave.

Figures 5 and 6 show two other simple circuit arrangements. The scheme shown in Figure 5 differs from the scheme in Figure 3 only by the fact that the inductive branch of the tuned output circuit contains a series condenser C. Figure 6 comprises a short-circuit path CiLi for the fundamental wave, in parallel relation to the oscillation circuit Cn, Ln for the useful wave. The latter circuit is tuned to the useful wave either alone or together with the short-circuit path C1, L1.

Generally speaking, ytwo different valves may be paralleled in opposition. As a result dissymmetric curves are obtained which may, though not necessarily, comprise a direct current component.

A considerable simplication in the arrangement together with greater efficiency is obtained if in lieu of the rectifiers reversing valves socalled are employed. Reversing valves are thermionic or ionic tubes' which, as shown, for instance, diagrammatically in Figure 7 comprise two heated filaments. The current in such a reversing valve is thus able to pass through in both directions, though it is distorted seeing that the valve does not work with a rectilinear characteristic. Hence, such a reversing valve can be regarded as a combination of two ordinary valves directly connected in opposition, each electrode of such reversing valve during one half-cycle playing the part of the cathode of one valve, and

during the following half`cycle the part of that t l. Means for multiplying the frequency of the oscillations derived from a source of alternating current potentials comprising a circuit coupled to said source, a bilateral thermionic rectifying device includng tubes having their electrode systems opposed and connected in parallel, said device being connected in series with said circuit, and means in said circuit for tuning a portion thereof to a harmonic of the frequency of said source.

2. An arrangement as claimed in claim 1 in which a. series circuit tuned to resonance at the fundamental frequency is connected in parallel with said tuning means.

3. Means for producing high frequency oscillations from a source of alternating current comprising a series circuit coupled to said source, a bilateral rectifying device including gaseous discharge electrode systems, each including an anode and a cathode, the anode of one system being connected to the cathode of the other system and the anode of the latter system being connected to the cathode of the first system, said device being connected in series with said circuit, and means for tuning a portion of said circuit to a harmonic of the fundamental frequency.

4. A high frequency generator and transmitter comprising a source of alternating current, a load circuit, a circuit inductively coupled on the one hand to the source of alternating current and on the other hand to the load circuit, a plurality of thermionic rectifiers, a circuit for connecting the anodes of some of said rectiflers to the cathodes of other of said rectifiers and the anodes of said other of said rectiers to the cathodes of said first named rectiers, thereby connecting'the internal mpedances of said rectifiers in parallel, a circuit for connecting said rectifiers in series with said rst named circuit, means for tuning a portion of said first named circuit to a harmonic of the fundamei'ital frequency, and a circuit tuned to series resonance at the fundamental frequency connected in parallel with the tuning means.

5. An arrangement as claimed in claim 4 in which the means for tuning the rst named circuit comprises capacity and inductance in parallel, and in which the series resonance circuit comprises capacity and inductance.

6. Means for multiplying the frequency of alternating currents comprising, a circuit having its input terminals coupled to said source of currents, a pair of thermionic rectifiers, each having an anode and a cathode, means for connecting said rectiers in parallel by connecting theanode of one of said rectifiers to the cathode of the other of said rectiers and the anode of said last named rectifier to the cathode of said flrst named rectifier, means for connecting said parallel connected rectiers in series with said circuit, and means for tuning the output of said circuit to a multiple of the frequency of said source.

7. The combination of a source of alternating current andmeans for producing oscillations 'of an increased frequency comprising, a circuit having an input inductance coupled to saidsource and an output inductance coupled to a load circuit, a rectier having its cathode connected to one terminal of said input inductance and its anode connected to one terminal of said output inductance, a second rectifier having its anode connected to the cathode of said rst named rectiner and its cathode connected to the anode of said rst named rectifier, and capacitive means for tuning said output inductance to a frequency greater than the frequency of said source.

RUDOLF GRTLER. 

